The oil and gas industry often requires tools which can be placed downhole. Some of these tools require an electrical power source to operate. To allow a tool to be easily maneuvered, the power source must fit inside of or be attachable to the tool. Because downhole tools are round and because interior space is limited, it is often impossible to use commonly available power source designs.
One of the more common portable power sources is a battery pack. These devices arc constructed of rigid plastic and provide semi-cylindrical ports for installing cells. Spring-loaded retaining clips hold the cells in place and maintain electrical contact with the cells. Internal electrical connections provide the appropriate interconnection between the cells. External electrical connections allow the user to draw electrical power from the battery pack. These battery packs are essentially in the shape of a rectangular parallelepiped. Rigid battery packs such as this cannot be used in many downhole tools. They are not suitable for mounting on the exterior of a tool because their shape, size, and rigidity would obstruct the travel of the tool through the drill hole. Similarly, their shape and size often precludes their use within the tight confines of the tool's interior.
One solution to these limitations is to mount cells between two rigid boards which fit the contour of the downhole tool. Battery packs made in this fashion may be mounted on the interior wall of a tool with the cells held parallel to the longitudinal axis of the tool. Such battery packs arc an improvement over the previously described battery packs, because they allow the cells to be held to the side. However, such a construction requires that a unique size of battery pack be manufactured for each tool size used. These battery packs have the additional disadvantage of only being mountable in a single orientation.
Another method of supplying electrical power is to mount a cylindrical tube in the downhole tool so that both cylinders share the same longitudinal axis. This tube-within-a-tube design allows cells to be stacked along the tool's longitudinal axis, with electrical contacts for supplying power at opposite ends of the stack of cells. This method shares the disadvantages of the other battery packs because it is rigid and must be manufactured to fit a particular tool size.
It is an object of the present invention to provide an electrical power source for use with downhole tools that may be mounted to the interior or exterior circumference of a tool.
It is another object of the invention to provide an electrical power source that is flexible and may be easily attached to a variety of downhole tools.
It is another object of the invention to provide an electrical power source that may be mounted to a downhole tool in a variety of orientations.
It is a further object of the invention to provide an electrical power source for use with oil tools which may be quickly electrically coupled and decoupled from a downhole tool.
It is another object of the invention to allow a downhole tool electrical power source to be quickly removed and attached to a different downhole tool.
It is a further object of the invention to allow an expended downhole tool electrical power source to be rapidly replaced.